In accordance with one aspect the invention relates to a pitted roll for the inking unit of an offset litho printing press, more particularly a short inking unit, which has pits which are separated from each other by lands containing a ceramic material and having a surface, preferably one of copper, with an affinity for ink, which roll is designed to cooperate with at least one doctor resting on its periphery and preferably set at a negative angle thereto.
A pitted roll of the this type has been proposed in U.S. Pat. No. 4,637,310. In the case of this known arrangement use is made of an engraved base member, which is provided with a dual layer coating following the engraved structure. The clearance width and the depth of the pits produced by engraving the base member are in this case altered by the following coating operation. There is thus the danger of an undesired departure from the desired dimensions, since it is not possible to produce the coating with a perfectly regular, i.e. accurate thickness. Apart from this, in the known arrangement, owing to the coating being carried out after the engraving operation, comparatively broad lands are produced, which is often undesirable. A further fact is that in this respect the lands only consist of ceramic material at their center parts and have borders of comparatively soft material, something that has an unfavorable effect on the resistance to wear which may be obtained. In the known roll the inner layer of the dual coating consists of ceramic material and the outer layer consists of copper, which is removed at the outer face and in the pits is left to form a lining.